The driver of a tractor needs to monitor and control a wide variety of parameters relating to both the operation of the tractor itself and the operation of an implement attached to the tractor.
To monitor the operation of the tractor, it is known to provide a cab display (CD) screen which is connected through a proprietary communications bus to a dedicated computer which receives signals from different sensors that are mounted on the tractor. The driver can select to display on the screen the information that is relevant to the operation being performed at the time. For example, if operating a plough, the driver may wish to monitor the operation of the three point hitch and, when operating such ancillary equipment as a mechanical shovel, he may wish to monitor the settings of the hydraulic circuits powering the equipment.
To monitor the operation of an implement coupled to the tractor, on the other hand, it is known to provide in the cab of the tractor a separate virtual terminal (VT) display which communicates with the implement using a bus complying with industry standard ISO 11783. Using an industry standard bus to establish communication between the VT display and the computer mounted on board the implement, allows the same display to be used with implements from different manufacturers.
Aside from the cost of providing two separate screens for the cab display and the virtual terminal, the prior art has the disadvantage of requiring the driver to gather information separately from two screens and to use different keypads or control panels to select the information and set the control parameters displayed on the different screens.
In a patent application filed on the same day as the present application, the Applicants have proposed an agricultural vehicle having a screen, a control panel associated with the screen and two data buses operating using different protocols connected in common to the screen and to the control panel to permit the screen to communicate with two computers mounted on board the vehicle and an implement connected to the vehicle, respectively, so as to allow the screen to display selectively data relating to both the vehicle and the implement.
By enabling a single screen mounted in the cab to act both as a CD and VT display, the invention allows the driver of an agricultural vehicle to monitor and set parameters in both the tractor and the implement without having to switch between screens and control panels.
While the latter proposal simplifies the monitoring of several operations, the need to be able to control different implements under different operating conditions still calls for a great deal of experience and skill.